Transcriptional control-proteins increase the rate of transcription by binding to

A.

MRNA sequences within the DNA.

B.

TRNA sequences within the DNA.

C.

Operator sequences within the DNA.

D.

Promotor sequences within the DNA.

E.

Enhancer sequences within the DNA.

3.

All regulatory proteins have common DNA binding motifs, which are particular bends in their protein chains that permit them to interlock with the

A.

Minor groove of the DNA helix.

B.

Major groove of the DNA helix.

C.

Outside groove of the DNA helix.

D.

Inside groove of the DNA helix.

E.

Hydrogen bonding groove of the DNA helix.

4.

Vertebrate cells apparently possess a protein that by binding to clusters of 5-methylcytosine ensures that the bound gene will stay in the "off" position. This control on the role of gene regulation is a result of

A.

Translation.

B.

Enhancer expression.

C.

Methylation.

D.

Promotor expression.

E.

Operator suppression.

5.

Regulatory proteins shut off transcription by binding to a site immediately in front of the promoter and often even overlapping the promotor. This site is referred to as the

A.

Suppressor site.

B.

Operator site.

C.

Repressor site.

D.

Regulatory site.

E.

Transcriptional control site.

6.

Histones are tightly packed into ______, which are located within the DNA.

A.

Operons

B.

Nucleosomes

C.

Clusters of proteins

D.

Repressor genes

E.

Facilitators sites

7.

Which of the following is the hallmark of multicellular organisms?

A.

Grow and divide rapidly

B.

Cells adjust quickly to outside environment

C.

Homeostasis

D.

Quickly synthesize amount and type of enzymes according to available nutrients

E.

Respond by gene action to oxygen availability

8.

Enhancers are the binding sites for the

A.

Promotors of DNA synthesis.

B.

Suppressor factors.

C.

Co-activation factors.

D.

Mediator factors.

E.

Specific transcription factors.

9.

The most common form of control of gene expression in both the prokaryotic and eukaryotic organisms is

A.

RNA processing control.

B.

Translational control.

C.

Protein phosphorylation control.

D.

Transcriptional control.

E.

MRNA degradation control.

10.

A nucleosome contains ____ histones within its core.

A.

2

B.

4

C.

6

D.

8

E.

64

11.

The basic tool of genetic regulation is the ability of certain proteins to bind to specific

A.

Regulatory RNA sequences.

B.

Regulatory DNA sequences.

C.

Repressor parts of the gene.

D.

Promoter parts of the gene.

E.

Enzymes of the cell.

12.

Which of the following is not true about control of gene expression?

A.

In bacteria it allows them to adapt to changing environments.

B.

In multicellular organisms it is critical for development.

C.

In bacteria it allows them to replicate without control.

D.

In multicellular organisms it allows them to maintain homeostasis.

E.

In multicellular organisms it allows them to function as a whole.

13.

RNA polymerase binds to a site on DNA called the

A.

Operator.

B.

Repressor.

C.

Footprint.

D.

Promoter.

E.

Operon.

14.

Proteins that bind to regulatory sequences have shapes that fit into the

A.

Promoter.

B.

Operator.

C.

Operon.

D.

Minor groove of DNA.

E.

Major groove of DNA.

15.

The DNA-binding proteins of almost all regulatory proteins employ one of a small set of shapes that enable them to fit into the major groove of DNA. These shapes are called

A.

Structural motifs.

B.

DNA prints.

C.

Operons.

D.

Repressors.

E.

Transcriptional domains.

16.

All of the following are examples of shapes in regulatory proteins which are used to bind to DNA except the

A.

Zinc finger.

B.

TATA box.

C.

Helix-turn-helix.

D.

Leucine zipper.

17.

In gene regulation, negative control is exerted by a(n)

A.

Activator.

B.

Operon.

C.

Promoter.

D.

Regulator.

E.

Repressor.

18.

In gene regulation, a gene is "turned on" by a(n)

A.

Activator.

B.

Stimulator.

C.

Promoter.

D.

Regulator.

E.

Repressor.

19.

A bacterial gene regulatory system is likely to have all of the following except

A.

A coding sequence.

B.

An operator.

C.

A promoter.

D.

One of more introns.

E.

A ribosome recognition site.

20.

Small RNAs can regulate gene expression. One type, called micro RNA (miRNA), acts by binding directly to

A.

MRNA to prevent translation.

B.

TRNA to prevent transcription.

C.

MRNA to prevent transcription.

D.

TRNA to prevent translation.

21.

Which of the following must happen for transcription to be initiated?

A.

DNA polymerase must have access to the DNA double helix and also must be capable of binding to the gene's promoter.

B.

RNA polymerase must have access to the DNA double helix and also must be capable of binding to the gene's promoter.

C.

DNA polymerase must have access to the RNA and also must be capable of binding to the gene's promoter.

D.

DNA ligase must have access to the DNA double helix and also must be capable of binding to the gene's promoter.

E.

DNA kinase must have access to the DNA double helix and also must be capable of binding to the gene's promoter.

22.

When E. coli cells produce the amino acid tryptophan, a cluster of five genes is transcribed together. This cluster of genes is referred to as the

A.

Trp transcriptional operator.

B.

Trp regulator.

C.

Trp suppressor.

D.

Trp operon.

E.

Trp promoter.

23.

The proteins necessary for the use of lactose in E. coli are collectively called the

A.

Lac regulator.

B.

Lac suppressor.

C.

Lac operon.

D.

Lac promoter.

E.

Lac transcriptional operator.

24.

Eukaryotic organisms

A.

Have their transcription occurring in the cytoplasm and translation in the nucleus.

B.

Have their transcription occurring in the nucleus and translation in the cytoplasm.

C.

Have only operons to assist in gene expression.

D.

Carry out protein synthesis only in the presence of the cAMP molecule.

E.

Use the leucine zipper primarily for the production of the amino acid tryptophan.

25.

Which of the following statements regarding primary transcripts in eukaryotes is correct?

A.

The primary transcript is composed of RNA polymerase and associated histones.

B.

The primary transcript has the exons removed and the introns retained for translation.

C.

The primary transcript is a faithful copy of the entire gene including exons and introns.

D.

The primary transcript is a faithful copy of the gene, but the introns have been removed.

E.

The primary transcript is a faithful copy, but the exons have been removed.

26.

The enzyme -galactosidase acts on lactose to form galactose. In turn, the presence of galactose leads to expression of the enzymes responsible for the metabolism of galactose. In this case, lactose is serving as a carbon source and as a(n)

A.

Inducer.

B.

Repressor.

C.

Effector.

D.

Operon.

27.

Which of the following statements regarding control of the lac operon and lactose utilization in bacteria is false?

A.

The lac operon controls the expression of three downstream genes.

B.

Bacteria preferentially utilize lactose as a carbon source.

C.

The lac operon will not be induced in the presence of both glucose and lactose.

D.

Control of the lac operon is negative, mediated by a repressor.

28.

You are studying the regulation of a prokaryotic operon. Experimental results suggest that the operon is governed by negative control. Based on this information, you conclude that

A.

The operon is ON in the absence of its regulatory protein.

B.

The operon is OFF in the absence of its regulatory protein.

C.

The presence of an inducer will always cause a repressor to bind the operator.

D.

The presence of an inducer will always prevent a repressor from binding the operator.